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shuns M. Penna-anon new A ORLEANS, LOUISIANA, ASS'IGNOR TO GEDRGE ,H ROBINSON, 1N TRUST FOR THE MFG COMPANY, OF NEW YORK, N.

FIRE) EXTINGUISHER MANUFACTUR- Y.

notation ro'nsxrineuisnine FlRF- SPECIFICATION forming part of Letters Patent No. 237,902, dated February 15,1881,

* I Application filed September 22, 1880. (No specimens.)

To-all whom @t may concern.-

Be it known that I, Janus M. Pennant), a citizen of the United States, residing at N ew Orleans, iii-the parish of Orleans and State of Louisiana, have invented-new and useful Improvements in Fire-Extinguishing Solutions,

'of which the following is a specification.

This invention relates to improved chemical compounds and combinations for generi o atiug carbonic-acid gas for producing pressure in the receivers oi chemical tire-extinguishers, and retaining the chemicals used for generating carbonic acid in solution with the 'water to increase the extinguishing power of .15 the latter, and also to avoid clogging the Yes i sols withinsoluble residuum.

lit is the object of my invention to dispense i tiiih the use of i'ree sulphuric acid in the neu 26 feet said neutralization by means of reagents in dry granulated or crystalline form, In

I using the neutral sulphate of alumina for this purpose, as heretofore, two dil'liculties have presented themselves, viz: First, the reaction,

when unassisted by heat, is too slow when it is necessary-to recharge the vessels dnrin the,

progress of fires; and, second, the sulphate'of aluminium that is, alumina (A1 0 after being deprived of its sulphuric acid-iiums an 0 insoluble hydrate of alumina, which settles in a gelatinous mass and is very troublesome to remove. t

By adding to the sodium bicarbonate a suitablequantity of boracic acid or biborate ct so- 5 dium in crushedycrystallmc form it is found that when the aluminium sulphate is neutralized by admixture of sodium bicarbonate the borax, by it's affinity forunetallic oxides, combines with the oxide of alumina and forms a 0 soluble-burrito of sodium and alumina, almost entirely preventing the formation of almuin ium hydrate. .[n using in this manner the borax the crushed crystals should bear the proportion of about fifteen per cent, by weight,

4 5 to one hundred sodium bicarbonate, or the borax may be exsiccated and used in dry powder, mingled with the sodium bicarbonate.

When boracic acidis used it may be minglad with either the alumina or soda, in which case there should be used a slight excess of soda, truth which it unites to form borax or the borate of sodium and aluminium, increasing the solubility of all the chemicals used.

. I have also added to the foregoing the acid sulphate of sodium (NaHSOg) or, as sometimes expressed, (Na SO,H SO This snltis a bisulphate of sodium, containing one equiva lent of sulphuric acid in excess; and, owing to its great solubility and the instant reaction when mixed with sodium bicarbonate, it can be used with ver great advantage mingled with the aluminium sulphate. This may be done in any proportions; but Ipref'er to use one-half sulphate gf alumina and one-halfbi-. sulphate oif'so'diu'm, and thus the quantity of oxide of alumina and resulting hydrate are of course reduced one-halt, and the solubility of the salts very greatly increased. Where extremely rapid action of the chemicals is desired the quantity of-bisulphate' of sodium is increased, and for some purposes it is better with no'admixtnre of the-aluminium sulphate.

When aluminium sulphate and sodium bisulphate are used together the sodium bicarbonate and biborate are mingled together.- The tendency of the hisulphate of sodium to absorb moisture from the air and separate into a neutral sulphate and freesulphuric acid is remediedby the admixture of an equal portion of aluminium sulphate, the latter salt being dry and porous, and absorbing the excess of acid in the sodium bisulphate.

The proportions of the chemicals used in charging a receiver are ordinarily about as fol- Iowa-the capacity ot the receiver being, say, 8 two hundred and lifty gallons: Bicarbonate of soda, seventy-five pounds; borax, twenty-five pounds, mixed; sulphate of aluminium, fifty pounds; bisulphate of sodium, fifty pounds, mixed. Themixedsoda bicarbonate and b-orax form one reagent, and the mixed aluminium sulphate and bisulphatc of sodium the other. These two reagents may be arranged in the receiver, and Water sufficient to iill thesame introduced in any ordinary or suitable manner.

As is weli known, chernioai fire-extinguishing engines become more etfectiveas the. solution thrown thereby becomes more heavily,

charged with chemicals, and any increase of the body of chemicals in solution is thus an improvement. The action of fire upon the improved solution which I have described is, 5 first, to evaporate the water of solution; next,

to expel the water of crystallization and combination, and then convert the sulphur to sulphurous-acid gas, which is a very powerful extinguisher ot' fire. The surface of every- IO thing touched by the solution is found, after the action of lire thereupon, to be covered by the oxides of aluminium and sodium, and al- I most fire-proof. 7 V r 1 Having now fully described my invention, 15 what I claim isv J. M. POLLARD. [1,. s.]

Witnesses: Y

JAMEsLLNoRRIs, or c J. HERMANN WAHLERS. 

